Scaffold.



PATENTED FEB. 28, 1905; R. G. JOHNSTON.

SCAFFOLD.

APPLICATION FILED MAY 6. 1904.

little. 783,837.

with Sairns Patented February 28, 1905..

lllaxr it it twang,

SCSAFl -"ULD.

SPECIFICATION forming part of Letters Patent No. 783,837, dated February28, 1905.

. Application filed May 6, 1904. Serial No. 206,657.

To It Hill/0772' it may concern: I

Be it known that I, ROBERT G. JOHNSTON, a citizen of the United States,and a resident of Clearmontjn the county of Nodaway and State ofli/lissouri,have invented a new and Improved Scaffold. of which thefollowing is afull, clear, and exact description.

My invention relates to temporary supports for workmen, beingparticularly adapted for the use of linemen while at work upon poles. Ithas for its principal objects the provision of a simple,easily-portable, and secure scaffold.

.lt consists in the various features and combinations hereinafterdescribed, and more particularly claimed.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar characters of reference indicatecorresponding parts in all the figures.

Figure 1 is a perspective view of a pole for supporting electricconductors with one embodiment of my invention applied thereto.

Fig. 2 is a top plan view of my device with the engaged member insection. Fig. 3 is a broken side elevation thereof, and Fig. 4 is atransverse section on the line 4t 4: of Fig. 2.

A designates the primary member of the support, which may consist of anintegral bar, preferably of steel or iron. havinga main portion 10 bentat one extremity at 11 to furnish a surface upon which to secure a seat12. This seat may be conveniently formed of sheet metal and preferablyhas its edges bent over at 13 to render it more comfortable for theuser. The opposite extremity of the main portion extends outwardly at14, it be ing here shown as curved, and carries at its outer end an arm15, which may rise at substantially right angles therefrom. This arm isitself bent at an angle to extend at 16, first, in the same generaldirection as the portion 10 of the support and then curved at 17, sothat its end lies in substantially the same plane as said main portion.At the extremity of this arm extending toward the portion 10 of thesupport is a sharpened engaging projection 18.

Mounted upon the supporting-bar is a contact member or bar B, which maycomprise a stem 19 and an enlarged portion or head 20, here illustratedas having separated branches or of a general it shape. This contactmember is adjustably retained in position upon the bar with the head inthe space formed by the curvature at 14: by means of securing memberswhich may conveniently consist of bolts 21, coacting with a longitudinalseries of openings 22, formed through the portion 10 of the support andthrough the stem of the contact member. One or another of these pairs ofopenings may be brought into reg istration and secured by the bolts andin this way the relation of the contact-head to the engaging projectionvaried.

The use of the device will be obvious from Fig. l of the drawings. Thelineman holding the supporting member with the seat in clined upwardlyplaces the projection behind the pole and then brings the member B downinto contact with the opposite sides. Then when weight is applied to theseat the contact member serves as a fulcrum, and by Vii" tue of theseparation between it and the projection the latter is forced into thepole, the greater the weight the lirmer being the cngagement. The spacebetween the branches of the Y causes them to engageconsiderablyseparated portions of the pole, serving to prevent lateraldisplacement. Thus it will be seen an extremely-secure support isobtained upon which the user may work safely. The vertical separationbetween the contact member and projection also permits the device to beapplied to a'considerable range of size of poles by the turning it to anangle thereto when putting in place; but when the resulting angle of theseat to the pole becomes too great for com fort or safety the contactmember may be adjusted upon the support to remedy this.

it will be further seen that my improved scaffold is comparativelyinexpensive to construct and while amply strong is so lighttl'iatit maybe readily carried by the user. It is also applicable to many otherpurposes than its use by linemen, such as that of carpenters inconnection with pole-barns and also as a support for stagings.

Having thus d escribcd my invention, I claim as new and d osi re tosecure by Letters Patent- 1. A scaffold comprisingamain bar having oneextremity extending outwardly from the side ofsaid bar and beingprovided with an engaging projection, extending toward the main bar, acontact-bar secured to the side of the main bar, and means for adjustingthe contact-bar along the main bar.

2. A scaffold comprising a bar extending at one extremity outwardly fromthe general plane otthe main portion, then substantially parallel tosaid plane, and finally back and being provided with an engagingprojection in alinement with the bar, and a contact member adjustable onthe main portion of the bar.

3. A scafiold comprising a main member having one extremity extendingoutwardly from the member, an arm carried by this extension and havingan engaging projection, said arm extending inwardly and leaving a spacebetween it and the outward extension, and a contact member mounted uponthe main member and having an enlarged portion situated adjacent to theextension of said main member and lying in the space between suchextension and the arm.

4. A scaffold comprising a main member having one extremity extendingoutwardly from the member, an arm carried by this extension and havingan engaging projection, said arm extending inwardly and leaving a spacebetween it and the outward extension, a contact member mounted upon themain member and having an enlarged portion situated adjacent to theextension of said main member and lying in the space between suchextension and the arm, and means for adjusting the position of thecontact member with relation to the engaging projection.

5. In a scaffold, the combination with a supporting-bar comprising amain portion, a curved portion and an angular arm, of a contact-barsecured to the supporting-bar and extending between the curved portionand the arm, the end of the contact-bar adjacent to said arm beingprovided with branches.

6. In a scaffold, the combination with a supporting-bar comprising amain portion, a curved portion and an angular arm, of a contact-barmounted upon extending along the supporting-bar and between the curvedportion and arm. said bars being each provided with a plurality ofopenings which may be moved into registration, and securing meansengaging the openings. I

7. A scaffold comprising a bar extending at one extremity outward fromthe general plane of the main portion, then substantially parallel tosaid plane and finally back and being provided with an engagingprojection opposite the bar, and a contact member adjustable upon themain portion of the bar and having branches at its inner end.

in testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

R-OB'ERT Gr. JOHNSTON.

lVitnesses:

J. M. SMITH, HENRY \VEBER.

